Electrochemistry - Free MCQ Practice Test with solutions, NEET NCERT Based

The E° in the given diagram is,

What is cell entropy change of the following cell?

Pt(s) | H₂(g) | CH₃COOH, HCl || KCl (aq) |Hg₂Cl₂| (s) | Hg

P = 1 atm        0.1M                0.1M

Emf of the cell is found to be 0.045 V at 298 K and temperature coefficient is 

3.4 x10^–4  VK^–1

Given Ka _(CH3COOH) = 10^–5 M

Following cell has EMF 0.7995 V.

Pt | H₂ (1 atm) | HNO₃ (1M) || AgNO₃ (1M) | Ag

If we add enough KCl to the Ag cell so that the final Cl^- is 1M. Now the measured emf of the cell is 0.222 V.

The K_sp of AgCl would be :

The solubility of [Co(NH₃)₄Cl₂] CIO₄_________ if the  = 50,  = 70, and the measured resistance was 33.5Ω in a cell with cell constant of 0.20 is ____.

We have taken a saturated solution of AgBr.K_sp of AgBr is 12 x 10 ^{– 14} . If 10 ^{– 7} mole of AgNO₃ are added to 1 litre of this solution then the conductivity of this solution in terms of  10 ^{– 7} Sm ^{– 1} units will be

[given  Sm² mol^-1 Sm² mol^-1, 5 x 10^-3 Sm²mol^-1]

At 298K the standard free energy of formation of H₂O(L) is – 237.20kJ/mole while that of its ionisation into H⁺ ion and hydroxyl ions is 80 kJ/mole, then the emf of the following cell at 298 K will be

 H₂(g,1 bar) | H⁺ (1M) || OH^– (1M) | O₂ (g, 1bar)

Which of the following cell can produce more electric work.

A hydrogen electrodes is immersed in a solution with pH = 0 (HCl). By how much will the potential (reduction) change if an equivalent amount of NaOH is added to the solution. (Take P_H2 = 1 atm) T = 298 K.

At what  does the following cell have its reaction at equilibrium?

 Ag(s) | Ag₂CO₃(s) | Na₂CO₃ (aq) || KBr(aq) | AgBr(s) | Ag(s)

 K_SP =  8 x 10 ^{– 12} for  Ag₂CO₃ and K_SP = 4 x 10 ^{– 13} for AgBr

Calculate the EMF of the cell at 298 K

Pt|H₂(1atm)|NaOH(xM),NaCl(xM)|AgCl(s)|Ag

If E°_cl-/AgCl/Ag = + 0.222 V

A current of 0.1A was passed for 2hr through a solution cuprocyanide and 0.3745g f copper was deposited on the cathode. Calculate the current efficiency for the copper deposition.

With t taken in seconds and I taken in Amp, the variation of I follows the equation

 t² + I² = 25

what amount of Ag will be electrodeposited with this current flowing in the interval 0-5 second ? (Ag : 108)

A resistance of 50Ω is registered when two electrodes are suspended into a beaker containing a dilute solution of a strong electrolyte such that exactly half of the them are submerged into solution. If the solution is diluted by adding pure water (negligible conductivity) so as to just completely submerge the electrodes, the new resistance offered by the solution would be

The standard reduction potential of a silver chloride electrode is 0.2 V and that of a silver electrode is 0.79 V. The maximum amount of AgCl that can dissolve in 10⁶ L of a 0.1 M AgNO₃ solution is          

Calculate the cell EMF in mV for

Pt|H₂(1atm) |HCl(0.01M)|AgCl(s)| Ag(s)        at 298 K

 If ΔG°r values are at 25°C

  for AgCl(s) and  for H⁺ + Cl^-) (aq)

Adiponitrile is manufactured electrolytically from acrylonitrile

 CH₂ = CHCN → CN – (CH₂)₄ – CN

How many kg of adiponitrile (molecular mass = 108) is produced in 9.65 hr using a current of 3750 A with 80% efficiency

It is observed that the voltage of a galvanic cell using the reaction M(s) + xH⁺→ M^x+ + X/2H₂ varies linearly with the log of the square root of the hydrogen pressure and the cube root of the M^x+ concentration. The value of x is       

Acetic acid has K_a = 1.8 X 10 ^{– 5} while formic acid had K_a = 2.1 X 10^–4. What would be the magnitude of the emf of the cell

Consider the cell Ag(s)|AgBr(s)|Br-(aq)||AgCl(s)|Cl-(aq)|Ag(s) at 25°C. The solubility product constants of AgBr & AgCl are respectively 5 X 10 ^{– 13} & 1 X 10 ^{– 10}. For what ratio of the concentrations of Br^- & Cl^- ions would the emf of the cell be zero ?           

Value of  for SrCl₂ in water at 25°C from the following data:

Calculate the useful work of the reaction Ag(s) + 1/2Cl₂(g) → AgCl(s)
Given  E°_cl2/cl- = + 1.36 V,       E°_AgCl/Ag,Cl- = 0.22 V

If         P_cl2 = 1 atm     and T = 298 K

Which of these ions Cu⁺, Co³⁺, Fe²⁺ is stable in aqueous medium.

Given :

E°_{Cu²⁺/Cu⁺} = 0.15 volt ;            E°_Cu⁺/Cu = 0.53 V ;       E°_{Co³⁺/Co²⁺} = 1.82 V ;

E°_{Fe³⁺/Fe²⁺} = 0.77 V ;   E°_Fe²⁺Fe = - 0.44 V ;    E°_{O²,H⁺/H²O} = 1.23 V

Select the correct statement if -

E°_Mg²⁺/Mg = - 2.4V,      E°_{Sn⁴⁺/Sn²⁺} = 0.1 V,     E°_{MnO^4-,H⁺/Mn²⁺} = 1.5 V, E° _I²/I^- = 0.5 V    Here,

 What is the value of pK_b (CH₃COOH^-) if λ_m^∞ = 390 & λ_m = 7.8 for 0.04 of a CH3COOH at 25°C          

The temperature coefficient of a standard Cd-cell is – 5.0X10^{– 5} Vk^{– 1} whose emf at 25°C is 1.018 V. During the cell operation, the temperature will -           

 A cell Ag | Ag⁺ || Cu⁺⁺ | Cu initially contains 2M Ag⁺ and 2M Cu⁺⁺ ions. The charger in cell potential after the passage of 10 amp current for 4825 sec is:          

For the cell (at 298 K)

Ag(s) | AgCl(s) | Cl^-(aq) || AgNO₃(aq) | Ag(s)

Which of the following is correct –

During an electrolysis of conc. H₂SO₄, perdissulphuric acid (H₂S₂O₈) and O₂ from in equimolar amount. The amount of H₂ that will form simultaneously will be (2H₂SO4 → H₂S₂O₈ + 2H⁺ + 2e^-)

Statement-1: In electrochemical cell, we cannot use KCI in the salt bridge if anodic  or cathodic compartment consists of Ag⁺ of Pb²⁺ ion.

Statement-2: Salt bridge is employed to maintain the electrical neutrality and to minimize the liquid-liquid junction potential.

Statement-1: Zinc protect the iron better than tin even after it cracks.

Statement-2: E°_OPzn < E°_OPfe But E°_OPSn > E°_OPfe